The last decade has seen dramatic advances in the field of endoscopic instrumentation, and the application of endoscopic techniques to a growing number of surgical procedures. The benefits--reduced pain and discomfort, shortened recovery time and better cosmetic results--insure that endoscopic surgery will continue to be a rapidly developing and widely applied technique.
Endoscopic surgery is performed with elongated instruments inserted through small holes in the skin, and is viewed through an endoscope. The image acquired by the endoscope is generally displayed on a video monitor. Endoscopic operations require more mental and physical dexterity than corresponding traditional surgical techniques. Because of these additional difficulties it is important to provide endoscopic instruments which are easy and convenient to use, and viewing systems which are as informative as possible.
Traditionally, endoscopes only utilize a single lens train and so only provide monoscopic viewing of surgical procedures. Since monoscopic views provide no depth information the surgeon must rely on foreshortening effects or tactile clues to determine depth relative to the viewing lens.